Copper–titanium decorated ternary interwoven network ZAC@CuO/TiO2@CNT as an efficient cathode catalyst in microbial fuel cells

The efficiency of air-cathode microbial fuel cells (MFCs) is restricted by the sluggish kinetics of the oxygen reduction reaction (ORR) at the cathode. Developing efficient catalysts to accelerate ORR and improve power generation is therefore a critical research priority. In this work, a copper–titanium bimetallic oxide (CuO/TiO 2 ) was synthesized via a one-step hydrothermal method and subsequently combined with ZnAlCu-layered double hydroxide (ZnAlCu-LDH) and carbon nanotubes (CNTs) to construct a ternary composite catalyst, ZAC@CuO/TiO 2 @CNT. Structural characterization revealed that ZnAlCu-LDH nanosheets uniformly adhered to CuO/TiO 2 layers, while CNTs interwove the nanosheets to form a conductive network, thus enhancing electron transfer pathways. The resulting material possessed a high surface area and porosity, facilitating oxygen diffusion and exposure of active sites. Electrochemical analysis demonstrated that ZAC@CuO/TiO 2 @CNT exhibited excellent ORR activity through a four-electron pathway. When applied as an MFC cathode, the catalyst achieved a stable output voltage of 350 mV over 260h, a maximum power density of 273.8 mW m −2 , a COD removal efficiency of 92.69 %, and a coulombic efficiency of 11.97 %. These findings highlight ZAC@CuO/TiO 2 @CNT as a cost-effective and environmentally friendly cathode catalyst, offering a promising strategy to enhance MFC performance and facilitate scale-up for practical applications. • Fabricate ZAC@CuO/TiO 2 @CNT via hydrothermal synthesis integrating LDH, oxides, and CNTs for ORR synergy. • Exhibit high surface area, porosity, and conductivity, facilitating charge transfer and electron transport. • Catalyze efficient 4e − ORR with superior stability in microbial fuel cells. • Deliver 273.8 mW m −2 power, 350 mV for 260 h, and 92.69 % COD removal, indicating strong practical potential.